Detergent compositions



United ttes DETERGENT CONHOSITIONS No Drawing. FiledApr. 12, 1956, Ser. No. 577 ,669

\ 17 Claims. (Cl. 252-153) The present invention relates to'dishwashing detergents, and particularly to specific detergent compositions char- "acterized by reduced tarnishing action towards metals, ""especially copper base alloys. An object of the present invention is the reduction of the discoloration and tarnishing of metals by certain detergent components, particularly non-ionic and anionic synthetic, organic detergent compounds. It is a further object of the invention to fprovide compositions containing the said components in the concentrations necessary in detergent formulations, "and to the improvement of such formulations by the combination therewith of a specific tarnish inhibitor.

- Another object of the invention is to provide detergent compositions"whichrnaybe employed in washing soiled -"cutlery"anddishes which remain in contact with the de ter'gentsolution for prolonged periods of time. It has been'found'that' cutlery articles, including knives, forks, --spoonsand"other tablewarernade of German silver: and sirrrilar copper basea'lloys', are normally discolored by solutions containing high concentrations of conventional,

, organic, non-ionic or anionic detergent compound. This is 'cor'nmonly observed in the washing of soiled cutlery and other household utensils consisting of copper base alloys, particularly during air drying, under which condi- --=tions-residual-amounts of detergent solutions may remain in contact withthe cutlery for prolonged periods of time. I For example, forks andspoons exhibit tarnishing at those contact points from which the residual solution is'evaporated at the conclusion of the washing operation. Plated cutlery made from a base of a copper alloy also exhibits this tarnishing if the plating is scratched or thin, and

*"such tarnishing action may be found on the entire piece of cutlery.

lt'hash'iovv' been found that the tarnishing or discolora- "tion effect upon'copper alloys; which is characteristic of non-ionic and anionic synthetic detergent compounds may be inhibited by the-combination therewith of benzazimidol in minor proportions suflicient to inhibit the said tarnish "ing. Apreferred proportion'of' benzazimidol employed to"reducediscoloration"and tarnishing in 'a' detergent composition is from 0.01% to 0.5% by weight based upon the synthetic organic detergent. The mechanism of the inhibitory-effect is not clear, but it has been found that relatively small proportions of ben'zazimidol are effective -in overcoming the tarnishing effect ofthe chemical compounds utilized in detergent compositions.

1 Benzazimidol was prepared by the reaction of hydrazine -hydrate. upon o-nitrochlorobenzene. The preparation was -carried out byplacing 157 g. (1 mole) of o-nitrochlorobenzene in a 500 ml. flask and adding thereto a mixture of 250 g. (2.5 mole) of hydrazine hydrate and 47 g.

of water." The reaction mixture was stirred and heated until refluxing began and was then maintained at reflux conditions for five and one-half-hours, during which time ;the pot temperature remained at 110-112 C. During "this'"period the original reaction charge changed from an oily,"t'wo phase system to a clear, red solution. At the conclusion of the reaction period, the reaction mixture atcnt O and filtered again.

"with 6 M HCl, giving a thick slurry. This was filtered to-yield a white solid, which was washed with ice-water The solid product was dried in a vacuum oven at 80 C. and was ground to give an almost white powder,weighing 120 g., M.P. 152-154 C. Upon polyglycerols.

cooling the 'filtratefrom the above final treatment, a further yield of 7.0 g. of the crystalline needles was obtained to give a total recovery of 127 g., corresponding to a yield of 93.8%. 'The analysis of the'ben'zazimidol, C H N O, was as follows: Analysis: C, 52.38; H, 4.23; N, 31.29. The calculated values for the above formula were: C, 53.3; H, 3.72; and N, 31.1.

The synthetic organic-anionic and non-ionic detergent components employed in the present invention include the sulfate and sulfonate type compounds as typical anionic detergents. Representative compounds of the non-ionic type are the others and esters (including sulfur-containing derivatives and analogues) of polyalkylene glycols and Mixtures of the above detergent components may also be employed.

The aliphatic sulfated or sulfonated detergents which are employed in combination with'benzazir'n'i'dol may have from 8 to 26 carbon atoms. Such detergents include the aliphatic, acyl-containing compounds having an acyl radical of about 8 to 26 carbon atom's such as the aliphatic carboxylic es te'r detergents. Examples of aliphaticam ionic detergents are the sulfuric acid esters'of polyhy- "dric alcohols incompletely esterified 'with'h'igher fatty acids,"for example, coco'anut oil mono-glyceride monosulfate, tallow diglycer'ideimonosulfate, the long-chain 'pure'or mixed higher, primary and secondary alkyl sulfates, such as lauryl sulfate, c'etyl'suIfat'eQand higher fatty acid alcohol sulfates derived from reduced cocoanut oil Other compounds 'wliiclfmaybe'used in combination with benzaziinidol include 'the hydroxy sulfonatedhigher fatty esters, forexamplqthe' higher fatty acid esters of 2,3-dihydroxy propane sulfonic acid, and

' the higher fatty esters of low molecular weight alkylol sulfonic acids, such as the oleic'estei' of ise'thionic acid. The invention also contemplatesthe use of higher fatty 'ethanolamide sulfates the higher'fatty' acid amides of amino alkyl sulfonic acids, 'for'example' lauric' 'ar'nide of taurine, etc. 'Thesaltsof the various compounds employed in the present invention are preferably the'sodium, ammonium or potassium salts.

One of the preferred types of detergent components is a sodium or ammonium sulfonate of an 'alkyl-substituted aromatic hydrocarbon selected from'the group consisting of benzene,toluene and xylene, wherein the alkyl group "has from 9 to 18 carbon atoms. 'The alkylaryl hydrocarbon is sulfonated and is then neutralized with a sodium, potassium or ammonium alkaline compound to obtain the corresponding sodium, potassium, or am monium salt. In the preparation of the alkylaryl sulfrom olefins or from kerosene.

dium tetrapropyl benzene s'ulfonate when-derived from tetrapropylene and benzene.

Other compounds of the above category of anionic detergents having utility in the present invention include the sulfated esters such as the sulfated esters of succinic acid and of sulfophthalic acid. Examples of such compounds which may be employed in the present detergent compositions are the sodium salt of dioctyl sulfosuccinate, sodium hexyl-4-sulfophthalate and octadecyl sulfophthalate. The present invention may also employ sulfonates of an acid which is esterified with a monohydric alcohol. A salt of this type of compound is sodium tridecyl fi-sulfopropionate.

Anotherm group of useful detergent compounds are the sulfated and sulfonated anionic detergents based on alkyl phenols or long chain, fatty alcohols and tall oil condensed with ethylene oxide or propylene oxide. Examples of such compounds are the sodium, ammonium or amine (e.g., triethanolamine) salts of nonyl phenol condensed with ten moles of ethylene oxide and then sulfatcd, while another compound is tridecanol condensed with ten moles of ethylene oxide and then sulfated.

The anionic detergents are generally employed in the form of water-soluble salts, such as the alkali metal salts described above. However, the alkaline earth metal, ammonium, amine, and alkylolamine salts are likewise of utility in the present invention. While the sodium, potassiurn, ammonium and alkylolamine (e.g., mono-, diand triethanolamine) salts are ordinarily preferred, other salts such as the lithium and magnesium salts may be used if desired. For certain purposes, as in the attainment of the maximum solubility, the ammonium and alkylolamine salts are preferred.

The non-ionic compounds which are employed in the present invention include the polyoxyethylene ethers of aliphatic alcohols having straight and branched chain configurations. Long chain derivatives of polyhydroxy compounds such as the ethers of polyalkylene glycols may also be employed in the present detergent compositions. Other compounds include the olyoxyethylene ethers of alkyl aromatic hydroxy compounds, for example, the alkylated polyoxyethylene phenols.

A typical compound of this group is the ethylene oxide condensation product of a highly branched monohydric primary alcohol such as tridecanol, having the molecular configuration of an alcohol produced by the x0 process from an olefin such as triisobutylene or tetrapropylene, with from 1 to 20 moles of ethylene oxide per mole of alcohol. A preferred range is from 5 to moles of ethylene oxide. The present invention includes the use of a mixture of isomeric monohydric primary tridecyl alcohols, said alcohols being derived from the Oxo process carried out with a material of the class consisting of polybutylenes and polypropylenes.

Another detergent component of the polyoxyethylene condensate type is the product obtained by the condensation of tall oil with ethylene oxide. The condensation of tall oil with ethylene oxide may be conducted with from 1 to 20 moles of ethylene oxide per mole of the tall oil, a preferred range being from 5 to moles of ethylene oxide. Another condensation product of this type which is useful in the present invention is the product resulting from the condensation of tertiary octyl or nonyl phenol with from 5 to moles of ethylene oxide per mole of the said phenol.

Polyoxyethylene compounds containing sulfur are also of utility. A compound of this type which may be employed in the present invention is the condensation prodnot of a tertiary mercaptan having from 6 to 20 carbon atoms, condensed with from 5 to 20 moles of ethylene oxide per mole of mercaptan.

The above described polyalkylene condensation products may be prepared from propylene oxide as well as with ethylene oxide. Admixtures of these two condensing agents may also be employed.

Another synthetic, organic detergent component which may be employed in the present invention is a compound selected from the group of'alkanolamides of fatty acids, preferably having from 10 to 20 carbon atoms. A preferred compound of this type is lauric diethanolamide derived from diethanolamine and crude lauric acid. Other acids and mixtures thereof may similarly be employed for this purpose. For example, an alkanolamide may be prepared from the fatty acids derived from tall oil during the purification and fractionation thereof. The alkanolamine which is employed to form the preferred alkylolamides may be monoor diethanolamine, monoor diisopropanolamine, or monoor di-n-propanolamine. Preferred amines are diethanolamine and mono-ethanolamine.

Other sources of fatty acids which may be used in the preparation of the alkylolamides are the naturally occurring fatty acids, such as those derived from cocoanut oil. The said cocoanut oil fatty acids are within the present preferred group of fatty acids having from 10 to 20 carbon atoms in the acid radical.

In addition to the above-described synthetic, organic detergent components, the present compositions may include builders such as inorganic phosphate and sulfate salts. The preferred amounts of builders are from one to twenty proportions by weight referred to the synthetic, organic detergent.

The present invention contemplates the formulation of detergent compositions including specific polyphosphates, preferred compounds being selected from the group consisting of tripolyphosphates, pyrophosphates, hexametaphosphates, tetraphosphates, and mixtures thereof. The sodium and ammonium salts are ordinarily employed, but the potassium salts may similarly be employed, particularly in the formulation of liquid detergent concentrates. Other inorganic salts such as the sodium silicates may also be utilized in the compositions of the present invention. Detergent builders and modifiers, for example, sodium sulfate, fluorescent dyes, perfume and carboxy methyl cellulose are likewise contemplated within the scope of the invention.

The following specific examples further illustrate the present invention.

Example 1 A composition consisting of an intimate mixture of the following ingredients was prepared, the proportions being based on the weights of the respective components. This A similar mixture without the benzazimidol was also prepared as a control.

The above detergent formulations were utilized in water at 0.25 weight percent concentration in order to determine the eifectiveness against metal discoloration or tarnishing. The tests were conducted upon small samples of German silver which had been polished with crocus cloth washed and rinsed in acetone. The metal test samples were tested in a half-submerged position in a beaker containing the detergent solution. The tests were conducted for a period of 24 hours at a temperature of approximately 70 F. At the conclusion of this time the metal samples were examined to determine the extent of the discoloration.

It was found that the above formulation containing benzazimidol did not appreciably discolor or tarnish the German silver. Under the same test conditions the corresponding formulation without the benzazimidol did :shows severe discoloration :rosion test .carried out .with distilled water in the absence are of particular utility in dishwashing.

oritarnishing. A blankicorof a detergent also showed discoloration.

ifzlExampl'e 2 Example 3 In tests conducted to determine the effective proportions of benzazimidol in order to resist tarnishing, a series of detergent mixtures were prepared. The active components were the ethylene oxide condensation product utilizing 8.5 moles of ethylene oxide with one mole of commercial tridecanol derived from the x0 process by the oxonation of a 12 carbon atom olefin. The discoloration tests were conducted upon samples of German silver prepared as described above. The results obtained are summarized below:

Benza- Trideeanol-E.O., Weight, Percent zimidol, 'Iamish Weight, (48 Hrs.) Percent 0.1.... 0 Severe. 0.1. 0.2 None. 0.1... 0 5 None.

The above data indicate that the combination of benzazimidol, together with a synthetic, organic detergent component resists the tarnishing effect which is otherwise characteristic of the detergent employed alone.

The detergent compositions of the present invention It is, accordingly, an embodiment of the present invention to wash cutlery in an aqueous washing solution. The preferred concentration of the present detergent composition containing benzazimidol is from 0.05% to 0.5% by Weight of the detergent product in the said dishwashing solution. The essential ingredient is the combination of a synthetic, organic detergent compound of the anionic or non-ionic type, together with a minor proportion of benzazimidol sufiicient to resist tarnishing of copper base alloys by the said detergent compound.

What is claimed is:

l. A detergent composition consisting essentially of a synthetic, organic detergent selected from the group consisting of the sulfated and sulfonated anionic and nonionic detergents, and in combination therewith a small amount of benzazimidol sufficient to inhibit tarnishing of a copper base alloy.

2. A detergent composition consisting essentially of a sulfated and sulfonated anionic, synthetic, organic detergent, and in combination therewith a small amount of benzazimidol sufficient to inhibit tarnishing a copper base alloy.

3. A detergent composition consisting essentially of a non-ionic, synthetic, organic detergent, and in combination therewith a small amount of benzazimidol sufiicient to inhibit tarnishing a copper base alloy.

4. A detergent composition consisting essentially of a sodium dodecyl benzene sulfonate, and in combination therewith a small amount of benzazimidol sufficient to inhibit tarnishing a copper base alloy.

5. A detergent composition consisting essentially of an ammonium dodecyl benzene sulfonate, and in combination therewith a smallamountofzbenzazimidolisufficient to inhibit tarnishing a copper base alloy.

6. A detergent composition consisting essentially of the condensation product of 1 to 20' moles'of ethylene oxide with! moleof tridecyl alcohol; and in combination therewith a small amount of benzazimidol' .sufiicient to inhibit tarnishing a copper base alloy.

7. A detergent composition consisting essentially of a synthetic, organic detergent selected from the group consisting of the sulfated and sulfonated anionic and nonionic detergents, and in combination therewith 0.01% to 0.5% of benzazimidol, based upon the said detergent, to inhibit tarnishing of a copper base alloy.

8. A detergent composition consisting essentially of a sulfated and sulfonated anionic, synthetic, organic detergent, and in combination therewith 0.01% to 0.5 of benzazimidol, based upon the said detergent, to inhibit tarnishing of a copper base alloy.

9. A detergent composition consisting essentially of a non-ionic, synthetic, organic detergent, and in combination therewith 0.01% to 0.5% of benzazimidol, based upon the said detergent, to inhibit tarnishing of a copper base alloy.

10. A detergent composition consisting essentially of a sodium dodecyl benzene sulfonate, and in combination therewith 0.01% to 0.5% of benzazimidol, based upon the said sulfonate to inhibit tarnishing of a copper base alloy.

11. A detergent composition consisting essentially of an ammonium dodecyl benzene sulfonate, and in combination therewith 0.01% to 0.5 of benzazimidol, based upon the said sulfonate to inhibit tarnishing of a copper b-ase alloy.

12. A detergent composition consisting essentially of a condensation product of 1 to 20 moles of ethylene oxide with 1 mole of tridecyl alcohol, and in combination therewith 0.0l% to 0.5 of benzazimidol, based upon the said condensation product to inhibit tarnishing of a copper base alloy.

13. An aqueous detergent bath having high detersive efliciency and being resistant to the tarnishing of a copper base alloy, consisting essentially of a synthetic, organic detergent selected from the group consisting of the sulfated and sulfonated anionic and non-ionic detergents, water, and in combination therewith about 0.01% to 0.5 by weight of benzazimidol, based upon the said detergent.

14. The method of washing cutlery which comprises subjecting said cutlery to an aqueous washing solution consisting essentially of a synthetic, organic detergent selected from the group consisting of the sulfated and sulfonated anionic and non-ionic detergents, water, and in combination therewith about 0.01% to 0.5% by weight of benzazimidol, based upon the said detergent.

15. The method of washing cutlery which comprises subjecting said cutlery to an aqueous washing solution consisting essentially of between about 0.05% to 0.5% by weight of a mixture containing as an active ingredient the condensation product of 1 to 20 moles of ethylene oxide with 1 mole of tridecyl alcohol, together with 0.01% to 0.5 by weight of benzazimidol, based upon the said condensation product.

16. A detergent composition consisting of the following ingredients in parts by weight:

Percent Ammonium lauryl sulfate 5-25 Lauryl diethanolamide 5-25 Ammonium dodecyl benzene sulfonate 5-25 Ammonium sulfate 0.5-5

Ethanol 025 Water 84.5-50

Benzazimidol 0.0l0.5

17. An aqueous detergent bath consisting essentially 7 8 of an aqueous solution of the composition defined in 2,618,608 Schaefier Nov. 18, 1952 claim 1. 2,733,215 Rufi Jan. 31, 1956 References Cited in the file of this patent 1 UNITED STATES PATENTS 5 OTHER REFERENCES 2,607,740 Vitale Au 19, 1952 Heilbron: 7 Dictionary of Organic Compounds, volume 2,618,606 Schaeifer Nov, 18, 1952 11, Oxford Univ. Press, NY. (1953), page 734. 

1. A DETERGENT COMPOSITION CONSISTING ESSENTIALLY OF A SYNTHETIC, ORGANIC DETERGENT SELECTED FROM THE GROUP CONSISTING OF THE SULFATED AND SULFONATED ANIONIC AND NONIONIC DETERGENTS, AND IN COMBINATION THEREWITH A SMALL AMOUNT OF BENZAZIMIDOL SUFFICIENT TO INHIBIT TARNISHING OF A COPPER BASE ALLOY. 